Carbon remover



Patented Mar. 7, 1939 UNITED STATES PATENT OFFICE" CARBON REMOVED wareNo Drawing. Application December 11, 1934,

I Serial No. 756,974

2 Claims.

This invention relates to improved compositions for removing orloosening carbon deposits such as occur in internal combustion enginesand other deposits of more or less related nature such as charred foodresidues, and is an improvement over the compositions disclosed inapplication Serial No. 609,030, new Patent 2,042,191, filed May 3, 1932by Hyym E. Buc and Raphael Rosen.

According to the original application referred to, an onium base wasused as a carbon remover. By the term onium base" is meant an organicbase in which monovalent organic radicals are connected to an inorganicelement to which, in

turn, an hydroxyl group is attached but to which no hydrogen atoms areattached. These onium bases may be considered to have the type formulaRnXOH in which Rn are organic radicals not necessarily the same and X isone of thevarious onium base elements such as nitrogen, arsenic,-

phosphorus, sulfur, iodine, and various metals, for example, tin,bismuth, antimony and other elements capable of forming onium compounds.

( In general, any of the elements in the righthand column of the 4th,5th and 6th groups of the periodic table are capable of forming suchonium compounds. The subscript n represents one less than the valance ofX. Thus the compounds used in .the present invention will be usually'either tertiary or quaternary hydroxides, depending upon the valence oftheonium base element.

The substituted radicals to be combined with the onium base element maybe any monovalent organic radicals and may comprise either the same ordifferent members in the same series, as methyl, ethyl; etc., or indifferent series, as alkyl, aryl, alcohols, or mixed or substitutedgroups. Also tertiary heterocyclic onium base compounds are suitable,for example, those of the pyridin type having a nitrogen atom in thering, and the homologs of such compounds. The chief require ment is thatall hydrogen atoms originally connected directly with the onium baseelement should be completely substituted by organic radicals.

Tetramethyl ammonium hydroxide is one of these onium bases which hasproved successful; other examples are:

These onium bases, have relatively high dis-- sociation constants of theorder of those of the alkali hydroxides and, according to the earlierapplication referred to, were found admirably suited when dissolved inwater, alcohol or other suitable solvent for loosening or removingcarbonaceous 5' gummy deposits from pistons, rings, and other parts ofinternal combustion engines, resulting from the partial evaporation anddecomposition of some of the lubricant.

It has been discovered and is a primary feature 10 of the presentinvention that the above described onium bases may be used in the formof emulsions in which form they possess certain advantages over theaqueous or alcoholic solutions previously disclosed. For instance,although the 16 aqueous solution of tetramethyl ammonium hydroxide doesnot corrode iron, steel, copper, zinc and other metals, yet it doescorrode aluminum and it has now been found that the corrosion ofaluminum is largely, if not completely, prevented 20 when the onium baseis used in the form of an emulsion prepared, for example, by emulsifyingan aqueous solution of the onium base with a small amount of oil and anemulsifying agent. Suitable emulsions have been prepared by incorporating 10 to 20% of an emulsifying agent, such as oil-solublesulfonates' derived by treatment of petroleum lubricating oil withconcentrated sulfuric acid, triethanolamine oleate orammonium rosinate,into an oil such as a refined lubricating oil and then forming anemulsion by mixing 25 to of the solution of emulsifier in oil with 65 to75% of 10% aqueous tetramethyl ammonium hydroxide. In general,oil-soluble sulfonates are preferred-as the emulsifying agent 35particularly those prepared according to the application of Hyym E. Buc,Ser. No.'626,233, filed' a July 29, 1932 now Patent 1,981,799. Theemulsions were found to be stable from 1 to 3 days or longer, in otherwords, long enough for the period 40 of time in which they are to beused and it was found that such emulsions practically"did not corrodealuminum at all. Y

Although the above described emulsions can be injected directly into theinternal combustlon, engine through .the spark plug holes or in anyother convenient manner without taking the engine apart, yet it ispreferred to take the pistons, rings, and other removable parts out ofthe engine and immerse them directly in a. pan or other suitable vesselcontaining" some of the onium base emulsion. These parts parts may alsobe contacted with the emulsion in any other suitable manner, such as byspraying} painting,

A suitable emulsion for such purpose may be prepared, for example, byemulsifying together equal volumes of a light petroleum oil such as thekind commonly used for flushing automobile engines and a 10% solution oftetramethyl ammonium hydroxide, using as the emulsifying agentoil-soluble sulfonates frequently called M soaps and derived bytreatment of petroleum distillates with concentrated sulfuric acid.

In addition to using the above described emulsions for removing carbondeposits from internal engines they may also be used for removing carbondeposits from ranges, oil burners, etc.

It has also been discovered that these onium base emulsions are adaptedto remove still other types of carbonaceous deposits such as charredfood residues from cooking utensils and are particularly useful forthose made of aluminum. For example, if vegetables such as beans orpeas, or fruits such as prunes, peaches, apricots, etc. are boiled inaluminum pans and through inadvertance the water is allowed to boil dryand the material being cooked becomes burnt it frequently happens thatsome of the charred residue adheres very tenaciously to the bottom andsides of the pan, so much so that even vigorous rubbing with abrasivematerials, such as certain soaps or wire brushes, steel wool, etc., willnot effectively remove the charred food residues without removing aconsiderable. portion of aluminum from the inside surface of the pan.Certain soaps or chemi cals having detergent effects have been usedoccasionally for such purposes but most, if not all, of those usedheretofore either are insufficiently efiective in removing the charredfood residue or else exert an objectionably harmful dissolving effeet onthe aluminum. The onium base emulsion,

prepared according to the present invention, has

been found very effective in removing such charred food residues fromaluminum cooking utensils without causing any substantial injury to thecooking utensil. As an example of such a use, an emulsion, prepared byemulsifying a 6% solution of tetramethyl ammonium hydroxide in watertogether with an equal amount of a 15% solution of oil-soluble sulfonatesoap in a light lubricating oil, was allowed to stand overnight at roomtemperature in an aluminum pan containing charred residue from burnedprunes and in the morning it was found that the charred residue had beencompletely loosened and was very readily removed with ordinary washing.

It is, of course, understood that this emulsion is also suitable forremoving charred food residues from other types of cooking utensils suchas enamel, granite, iron, etc. or any other surfaces with which theseresidues may be in contact, such as the top of burners or other parts ofcooking stoves, although, if desired, an aqueous or alcoholic solutionof the onium base may be used for removing charred food residues fromsuch surfaces.

It is not intended that the invention be limited by any of the specificexamples given but in the appended claims it is intended to claim allinherent novelty in the invention as broadly as the prior art permits.

We claim:

1. A carbon remover in emulsion form consisting of about 25-35% leumlubricating oil solution of oil soluble sulfonates derived by treatmentof a petroleum lubricating oil with concentrated sulfuric acid, andabout -75% of a 10% aqueous solution of tetramethyl ammonium hydroxide,said oil solution and aqueous solution being emulsified together.

2. A carbon remover in emulsion form consisting of about 25 to 35% of a10 to 20% refined petroleum lubricating oil solution of oil solublesulfonates derived by treatment of a petroleum lubricating oil withconcentrated sulfuric acid, and about 65 to of a 10% aqueous solution ofan organic onium base compound having dissociation properties equivalentto that of tetratmethyl ammonium hydroxide, said oil solution andaqueous solution being emulsified together.

EUGENE LIEBER. WILLIAM H. SMYERS.

of'a 10-20% refined petro-'

